You can use several variations: 1. You can use the verb "viajar" and the preposition "a": "A que países has viajado?" 2. You can use the verb "visitar", it doesn't use a preposition like "viajar a": "Qué países has visitado?" 3. You can use what another member already wrote, the verb "estar" and the preposition "en" (this one is the closest to "been to"): "En que países has estado?" 4, Or you can use what yet another member wrote, the verb "conocer": "Qué países conoces?" 5. Finally, you can use the verb "ir" (to go), and the preposition "a": "A qué países has ido?" Buena suerte, espero que esto amplíe tus capacidades de expresarte. Bye!

¿Qué países conoces?

Thank you!

¿En qué países has estado?